The DAB broadcasting system (Digital Audio Broadcasting, described in ITU COM '89, Geneva, Oct. 1989, and in Kunftige Systeme der digitalen Horfunkubertragung", Bayerischer Rundfunk, November 1990) has been developed to permit servicing of individual regions with a plurality of broadcasting programs. The DAB system provides a multiplicity of individual synchronized transmitters each of which respectively transmits six digital stereo sound signals in bit-synchronism in a COFDM signal packet (Coded Orthogonal Frequency Division and Multiplexing). Under the COFDM principle the digital data stream of the stereo signal is divided prior to transmission into a multiplicity of subsignals each of which is separately transmitted by a single carrier. In the receiver these subsignals are recombined to result in an overall information of the digital stereo signal. It is a further feature of the DAB system that the stereo signals to be transmitted, prior to COFDM processing, are correspondingly reduced with regards to their data quantity in accordance with a method that utilizes the psycho-acoustic phenomena of the human ear (MUSICAM=Masking Universal Subband Integrated Coding and Multiplexing, described in "An Universal Subband Coding System Description", CCETT IRT Matsushita and Philips).
This DAB system which was developed for audio broadcasting exhibits extremely good transmission characteristics. Moreover, it solves the problem of distortions of the radio signals in such synchronized networks due to transmission distances of different lengths and the resulting expected interferences.